The right rj45 connector for solid wires and stranded ones (like a mini rope)

Hey!

I've just noticed (after god knows how many years)... that rj45 plugs differ from one another. Some have 2 pronged pins and other 3 pronged ones. I've been reading for information on this and some say that:

Pins with 2 points can be used for solid and stranded.

Pins with 3 points can only be used for stranded wires?